166581655447 has 2 divisors, whose sum is σ = 166581655448. Its totient is φ = 166581655446.

The previous prime is 166581655423. The next prime is 166581655463. The reversal of 166581655447 is 744556185661.

166581655447 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166581655447 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166581655391 and 166581655400.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166581655547) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83290827723 + 83290827724.

It is an arithmetic number, because the mean of its divisors is an integer number (83290827724).

Almost surely, 2^166581655447 is an apocalyptic number.

166581655447 is a deficient number, since it is larger than the sum of its proper divisors (1).

166581655447 is an equidigital number, since it uses as much as digits as its factorization.

166581655447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192000, while the sum is 58.

The spelling of 166581655447 in words is "one hundred sixty-six billion, five hundred eighty-one million, six hundred fifty-five thousand, four hundred forty-seven".